Ankle pain is a frequent complaint in clinical practice, commonly linked to injuries like sprains or chronic conditions such as arthritis and tendinopathy. However, in some rare cases, the underlying issue may not be musculoskeletal but vascular—specifically, an ankle hemangioma, a benign tumor composed of blood vessels. Although hemangiomas are among the most common soft tissue tumors in infants, their occurrence in the adult ankle is unusual and often under-recognized.

When these vascular tumors develop around or within the ankle joint, they can be difficult to detect due to non-specific symptoms and their anatomical obscurity. Nevertheless, if left undiagnosed or untreated, they may interfere with mobility, cause pain, or mimic more severe pathologies like malignancies. Ankle hemangiomas, despite being benign, may therefore demand a more sophisticated diagnostic and therapeutic approach than their name might suggest.

What Is a Hemangioma?

A hemangioma is a non-cancerous tumor made up of blood vessels that grow abnormally. These growths may appear in various tissues and are usually categorized based on the size and type of blood vessels involved. Hemangiomas are most commonly associated with superficial skin lesions in infants, but they can also form in deep tissues, including muscles, bones, and joints.

When hemangiomas occur in deep structures like the ankle, they are less likely to be noticed early. They are typically discovered when they begin to cause discomfort, swelling, or disrupt movement. These deep lesions can be harder to classify and treat, especially when entangled with nearby nerves or joint components.

Types of Hemangiomas

In the ankle, intramuscular and cavernous hemangiomas are most frequently observed. These types grow inside or near muscles and can displace or compress surrounding structures such as tendons and blood vessels.

How Rare Are Ankle Hemangiomas?

While hemangiomas in general are relatively common in pediatric populations, their presence in the ankle joint of adolescents or adults is rare. Studies indicate that less than 1% of all soft tissue tumors occur in the ankle region, and only a fraction of these are vascular in nature.

One multicenter retrospective review found that among patients diagnosed with intramuscular hemangiomas, only around 18% had lesions in the lower extremities, and even fewer were localized near a joint like the ankle. This rarity increases the likelihood of initial misdiagnosis and underscores the importance of considering vascular tumors in the differential diagnosis of unexplained ankle swelling or pain.

Clinical Presentation: Symptoms and Signs

Ankle hemangiomas often manifest in subtle ways, with symptoms that may overlap with more common ankle issues. They can remain asymptomatic for months or even years, gradually becoming problematic as they increase in size or encroach upon surrounding tissues.

Common symptoms include:

• A soft, compressible mass:
  Patients may notice a small, squishy swelling near the ankle that feels like it can be pushed down. These masses often enlarge when standing or during physical activity due to increased blood flow into the tumor.
• Localized pain or discomfort:
  The pain is often dull and intermittent but may intensify with prolonged walking, running, or standing. This discomfort is typically not relieved by rest or conventional ankle supports, differentiating it from overuse injuries.
• Swelling or fullness:
  Chronic swelling that does not respond to anti-inflammatory medications may point to a vascular lesion. The swelling may become more noticeable toward the end of the day due to gravity-related pooling of blood.
• Warmth or bluish discoloration of the skin:
  If the hemangioma is superficial or close to the skin, a slight color change or a feeling of warmth may be present. This indicates increased vascularity in the area.
• Restricted range of motion:
  When the tumor impinges on tendons, ligaments, or joint capsules, it can physically limit the ankle’s ability to move freely. In these cases, stiffness or clicking may be reported.

In less common scenarios, hemangiomas can irritate adjacent nerves, producing numbness, tingling, or even muscle weakness in the foot or ankle.

Diagnostic Challenges and Imaging

Diagnosing ankle hemangiomas is inherently difficult due to their rarity and symptom overlap with more prevalent musculoskeletal conditions. They are frequently mistaken for ganglion cysts, bursitis, or tendinopathies, delaying accurate diagnosis.

Imaging Modalities

Magnetic Resonance Imaging (MRI) provides superior contrast resolution and is the most informative modality. On MRI, hemangiomas often appear as hyperintense lesions on T2-weighted images due to their high water content and blood pooling. They may also show internal septations or phleboliths (small calcifications) in older or cavernous lesions.

In superficial cases or where MRI is not available, Doppler ultrasound can still reveal vascular flow within the lesion, distinguishing it from avascular masses like cysts.

Differential Diagnosis

Given their rare and ambiguous presentation, ankle hemangiomas must be differentiated from other soft tissue masses or pathologies that affect the ankle. These include:

• Synovial Sarcoma:
  A malignant soft tissue tumor that may present similarly on imaging. Unlike hemangiomas, synovial sarcomas often show more aggressive borders and can invade bone.
• Ganglion Cyst:
  Commonly seen on the dorsal foot and ankle, ganglion cysts are fluid-filled and non-vascular. They are typically firm, non-painful, and show no internal blood flow on ultrasound.
• Venous Malformation:
  While often confused with hemangiomas, venous malformations are congenital, slow-flow vascular anomalies. They are less proliferative and do not regress or change as hemangiomas sometimes do.
• Lipoma or Fibroma:
  These soft tissue tumors are usually non-painful and non-vascular, showing distinct fat signals on MRI. They are typically less associated with swelling or functional impairment.

Because of the risk of misdiagnosis, a biopsy is generally avoided unless malignancy is strongly suspected, as puncturing a hemangioma could result in significant bleeding.

Treatment Options: A Nuanced Decision

The management of ankle hemangiomas is individualized, depending on lesion size, location, symptoms, and the patient’s functional needs. Not all hemangiomas require active treatment.

Observation

• For asymptomatic or small hemangiomas, observation is often sufficient.
  Patients undergo periodic imaging to ensure the lesion is not growing or interfering with mobility. This conservative strategy avoids unnecessary interventions.

Pharmacologic Therapy

• Used mainly in pediatric cases, medications like oral beta-blockers (e.g., propranolol) can shrink hemangiomas by constricting blood vessels and slowing cell growth.
  However, these are rarely effective for adult or intramuscular lesions and are seldom used in ankle cases.

Sclerotherapy

• Sclerotherapy involves injecting a chemical agent that irritates and collapses the blood vessels within the hemangioma.
  It is a minimally invasive option, typically used for venous-dominant hemangiomas. Success depends on the depth and accessibility of the lesion.

Surgical Excision

• Surgery is considered for painful or function-limiting hemangiomas, or when there’s diagnostic uncertainty.
  Surgical removal can be curative, especially when the tumor is well-circumscribed. However, because of the ankle’s complex anatomy, surgery must be meticulously planned to avoid damage to nerves, tendons, and blood vessels.

Post-Treatment Recovery and Risks

Recovery depends on the treatment approach and the lesion’s impact on nearby tissues. Patients undergoing surgical excision usually require a rehabilitation period lasting several weeks to months.

Post-treatment considerations include:

• Recurrence:
  Incomplete removal, particularly in infiltrative or poorly demarcated hemangiomas, can lead to regrowth. Routine imaging may be necessary for monitoring.
• Infection or delayed healing:
  Surgical sites, especially in the lower extremities, carry a risk of infection. Proper wound care and early mobilization under supervision are essential.
• Nerve or tendon injury:
  The close proximity of hemangiomas to neurovascular bundles in the ankle increases the risk of accidental damage during surgery. Such complications may result in transient or permanent deficits.
• Residual discomfort or stiffness:
  Some patients may experience lingering tightness or a reduced range of motion even after successful treatment. Physical therapy plays a vital role in full functional recovery.

For those undergoing sclerotherapy, skin irritation, pigmentation changes, or temporary swelling may occur. These side effects are typically self-limiting.

Tips for Patients and Clinicians

• Do not ignore persistent, unexplained ankle symptoms:
  Especially when typical treatments like rest or NSAIDs fail, consider imaging to explore less obvious causes like vascular tumors.
• Push for comprehensive imaging if symptoms linger:
  An ultrasound might not reveal deep lesions, so an MRI is often needed for a complete picture. Delaying appropriate imaging may complicate eventual treatment.
• Weigh risks and benefits before proceeding with surgery:
  Given the potential for complications, surgical treatment should be reserved for patients whose symptoms significantly impact quality of life.
• Consult specialists with experience in vascular anomalies:
  Not all orthopedic surgeons are trained in managing vascular tumors. A multidisciplinary team—ideally including vascular surgeons or radiologists—ensures safer, more effective care.
• Maintain follow-up and track symptom progression:
  Even if observation is chosen, patients should attend regular follow-ups to monitor for changes in lesion size, pain levels, or functional impact.

Conclusion

Though rare, ankle hemangiomas represent an important consideration in the differential diagnosis of chronic ankle pain, swelling, or mass lesions. Their atypical presentation can easily be overlooked, leading to prolonged discomfort or inappropriate treatment. Understanding the biology, imaging characteristics, and treatment nuances of hemangiomas allows for accurate diagnosis and personalized management.

When identified and managed appropriately—whether through observation, minimally invasive techniques, or surgery—patients with ankle hemangiomas can expect favorable outcomes and a return to normal activity. Greater awareness among clinicians and patients alike can help ensure these rare but impactful tumors are addressed with the care they require.

References

1. Enzinger, F. M., & Weiss, S. W. (2013). Soft Tissue Tumors (6th ed.). Elsevier Health Sciences.
2. Beham, A., & Fletcher, C. D. M. (2002). Intramuscular angioma: a clinicopathological analysis of 74 cases. Histopathology, 41(1), 1–10.
3. Dubois, J., & Garel, L. (1999). Imaging and therapeutic approach of hemangiomas and vascular malformations in the pediatric age group. Pediatric Radiology, 29(12), 879–893.
4. Legiehn, G. M., & Heran, M. K. (2008). Venous malformations: classification, development, diagnosis, and interventional radiologic management. Radiologic Clinics of North America, 46(3), 545–597.
5. Martel, W., & Hayes, R. (1982). Vascular malformations and hemangiomas: A review for radiologists. Skeletal Radiology, 8(4), 281–288.
6. Brill, R., Kammen, B. F., & Haller, J. O. (2001). MRI of hemangiomas in children: Correlation with pathologic findings. Pediatric Radiology, 31(12), 845–854.